Pope Francis will undergo an operation for an abdominal hernia on Wednesday at a Rome hospital, where he is expected to stay for "several days", the Vatican said.

The 86-year-old pope, who underwent colon surgery in 2021, is suffering from a hernia which is "causing recurrent, painful and worsening" symptoms, Vatican spokesman Matteo Bruni said in a statement.

It followed a brief visit to the Gemelli hospital in Rome on Tuesday, during which the Vatican said he underwent "clinical tests".

Francis led his weekly general audience as usual Wednesday, before preparing to head to the Gemelli.

"In the early afternoon he will undergo a laparotomy and abdominal wall surgery... under general anaesthesia," Bruni said.

A laparotomy is a surgical incision into the abdominal cavity.

"The stay at the health facility will last several days to allow the normal post-operative course and full functional recovery," the Vatican said.

Francis, who has been the leader of the world's 1.3 billion Catholics for a decade, has suffered increasing health issues over the past year.

In 2021 he underwent surgery at Gemelli for a type of diverticulitis, an inflammation of pockets that develop in the lining of the intestine.

Francis was also hospitalised for three nights at the end of March with bronchitis, which was cured with antibiotics.